const nodeList = [];
const ctx = '@@clickoutsideContext';

let startClick;
let seed = 0;

document.addEventListener('mousedown', e => (startClick = e), false);
document.addEventListener('mouseup', e => {
  nodeList.forEach(node => node[ctx].documentHandler(e, startClick));
}, false);

function createDocumentHandler(el, binding, vnode) {
  return function(mouseup = {}, mousedown = {}) {
    if (!vnode ||
      !vnode.context ||
      !mouseup.target ||
      !mousedown.target ||
      el.contains(mouseup.target) ||
      el.contains(mousedown.target) ||
      el === mouseup.target ||
      (vnode.context.popperElm &&
      (vnode.context.popperElm.contains(mouseup.target) ||
      vnode.context.popperElm.contains(mousedown.target)))) return;

    if (binding.expression &&
      el[ctx].methodName &&
      vnode.context[el[ctx].methodName]) {
      vnode.context[el[ctx].methodName]();
    } else {
      el[ctx].bindingFn && el[ctx].bindingFn();
    }
  };
}

/**
 * v-clickoutside
 * @desc 点击元素外面才会触发的事件
 * @example
 * ```vue
 * <div v-element-clickoutside="handleClose">
 * ```
 */
export default {
  bind(el, binding, vnode) {
    setTimeout(() => {
      console.log('bind reeee' );
      nodeList.push(el);
      const id = seed++;
      el[ctx] = {
        id,
        documentHandler: createDocumentHandler(el, binding, vnode),
        methodName: binding.expression,
        bindingFn: binding.value
      };

    }, 0);

  },

  update(el, binding, vnode) {
    if (!el[ctx]) return;
    el[ctx].documentHandler = createDocumentHandler(el, binding, vnode);
    el[ctx].methodName = binding.expression;
    el[ctx].bindingFn = binding.value;
  },

  unbind(el) {
    let len = nodeList.length;

    for (let i = 0; i < len; i++) {
      if (nodeList[i][ctx].id === el[ctx].id) {
        nodeList.splice(i, 1);
        break;
      }
    }
    delete el[ctx];
  }
};
